---You may find the key to the maths problem on page 107 .
---Ah, it’s so simple . I wonder why I of that .
| A．hadn’t thought | B．haven’t thought |
| C．didn’t think | D．wasn’t thinking |
Earth Day is celebration of life and our planet. It is a reminder that we need to________the world we live in and that we should learn to respect life and nature.
| A．care about |
| B．think of |
| C．refer to |
| D．watch out |
There isn't much money left. We must ________our spending.
| A．increase |
| B．prevent |
| C．rise |
| D．limit |
I ________back the money.
| A．rely on him to pay |
| B．rely on his paying |
| C．depend on him to pay |
| D．all the above |
He hurried to the booking office, only________that all the tickets had been sold out.
| A．to tell |
| B．to be told |
| C．telling |
| D．told |
She ________a chain to the dog's collar.
| A．granted |
| B．kept |
| C．attached |
| D．beard |